When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Interdasting cause over the many years and years of the M-S folks looking into this, no one has ever been able to confirm that the MSM actually see's or records or references boost in any meaningful way. (as in, it actually see's the 6-8psi that it makes when in OL)
MSM_MAP(psi)=7.811*(MAP_V)-5.764 @25°C and 250m above sea level
Cool. So then it does reference map/boost? do you have a plot or log to show us?
In the current version Forscan shows boost( MSM_MAP(psi)=7.811*(MAP_Voltage)-20.464 ) despite PID name is MSM_MAP( MSM_MAP(psi)=7.811*(MAP_V)-5.764 ).
I will ask Forscan developers change the PID name in the next revision.
and it reads second IAT(after intercooler) on MSM(this is not actual for aftermarket ECU owners )
Necro thread resurrection; does anyone know if there's a 2- or 3-bar sensor that is physically plug n play on the OEM harness? Rev has confirmed that the MS3 mini can read the stock baro sensor. I would prefer to run a short line from the IM and use this as a MAP with the on-board sensor on the MS3 acting as a baro correction device (yeah I am ---- like that).
The Baro sensor on that comes on the Miata is part of the pollution control system. It is called a boost sensor, but it is only a little over 1 BAR. I am using it for my Baro sensor. So no, you cannot connect it to the IM and use it for MAP. You have to do it the other way around. Use the onboard for MAP, and the other for baro.
It might work on a naturally aspirated motor, definitely not on a turbo one.
If you really want to avoid running vacuum lines or additional wires through the firewall you could remove the OEM MAP sensor and install an off-board sensor (like the GM 3-bar one) in its place. You would need to adapt the wiring harness somehow, ideally by sourcing the proper connector to build a short adapter harness.
@DNMakinson thanks! I am aware of that; this thread prompted my question, hence my post here.
Originally Posted by codrus
It might work on a naturally aspirated motor, definitely not on a turbo one.
If you really want to avoid running vacuum lines or additional wires through the firewall you could remove the OEM MAP sensor and install an off-board sensor (like the GM 3-bar one) in its place. You would need to adapt the wiring harness somehow, ideally by sourcing the proper connector to build a short adapter harness.
--Ian
Exactly what I was thinking; just wondering if there was any electrically compatible 3 bar sensor out there that would save me the "hassle" of building an adapter harness. Reasoning is that it would be cleaner/easier than running a vacuum line to the MS.
OK. I am pretty sure that there are (2) allowable external MAP sensors allowed on the MS3 Basic; but I don't know about the mini. Point being, that just because the mini can read the Baro, does not mean it can be mapped to the MAP input. Just not sure.
Good point (that I have not thought of); I was thinking that as soon as it reads that as input, it should be able to. Will report back once I find out (ECU sitting in a box for the past 8 months now)
Exactly what I was thinking; just wondering if there was any electrically compatible 3 bar sensor out there that would save me the "hassle" of building an adapter harness. Reasoning is that it would be cleaner/easier than running a vacuum line to the MS.
What do you mean by "electrically compatible"? I doubt you'll find a 3 bar sensor that has the Mazda connector on it, if that's what you're asking.
You don't really care about the response curve (volts per unit of pressure) because you're not going to run it with the stock ECU, right?
The voltage supplied to the sensor might be an issue. I *think* the GM sensor takes 5 volts in, but I don't know what Mazda supplies to the OEM sensor. That might be an issue.
Would like to avoid cutting the plug off the loom, but may just do that. Do not care about calibration, as indeed will be using a standalone ECU. Pretty sure the stock one is 5V, will verify and report back. Thank you all for your inputs!